Improvement in apparatus for roasting ores



2 Sheets-Sheetl. A. B. CROSBY. APPARATUS FOR ROAS'IING ORES.

No. 195,581. Patented Sept.25,1877.

W k f M T NPHERS. FHOTO-LXTHOGRAFHER. WASHINGTONv D C.

2 SheetsrSheet 2.

Patented Sept. 25, 1877.

NAFEIERS, PHOTO-UTHOGRAPHER. WASHINGTON, D c

UNITED STATES PATENT QFEIGE.

AUGUSTINE B. CROSBY, OF GREENE, MAINE, ASSIGNOR TO UNITED STATES GOLD AND SILVER AMALGAMATING COMPANY, OF VIRGINIA.

IMPROVEMENT IN APPARATUS FOR ROASTING ORES.

Specification forming part of Letters Patent No. l95,58l, dated September 25, 1877; application filed January 29, 1877.

To all whom it may concern:

Be it known that I, AUGUSTINE B. CROSBY, of Greene, Androscoggin county, Maine, have invented a new and useful Improvement in Apparatus for Boasting Ores, of which the following is a specification:

The main object of my invention is the complete oxidizatiou of what are known as diflicult or obstinate gold-bearing ores, such as sulphurets of iron, copper, and other base metals and ores, with which are associated arsenium, selenium, antimony, tellurium, 8m, in variable proportions, my invention being such that the gold or other precious metals shall be automatically and economically liberated and metallized without loss.

In the accompanying drawing, Figure 1,

Sheet 1, is a side view, partly in section, of apparatus wherewith I carry my invention into effect; Fig. 2, a vertical section of part of Fig. 1; Figs. 3 and 4, detached views of parts of the roasting-cylinder; Fig. 5, Sheet 2, a sectional plan of the apparatus; and Fig. 6, a sectional plan of part of Fig. 5, showing the bearing-rollers for the roasting-cylinders.

There are two main structures comprised in the apparatus-namely, the structure A, containing the roasting appliances, and the structure B,containing the settling-chambers. Within the latter is a compartment, A for the preliminary drying of the granulated ore in amanner which will be rendered apparent hereinafter, the dried ore being directed from this compartment through an opening, I), to the buckets of an endless elevator, 0, these buckets discharging their contents at an elevated point into the upper ends of a conduit,D,which directs the ore to the hopper-E; and below the outlet of the latter is a hopper-bag or feed-regulator,

F, from which the ore is fed through twotubes, G G, into the open ends of two roasting-cylinders, H H. Each cylinder has two bands or collars, e c, the collars e of the two cylinders bearing upon the peripheries of the rollers I, the journals of which are adapted to bearings on the walls or frames J J, the journals being maintained in a comparatively cool condition by a pipe, m, Fig. 6, through which cold water is caused to circulate. The collars e of the roasting-cylinders H bear on the peripheries of the flanged rollers I, the shafts of which have their hearings on the frame-work K, bevel wheels on the shaft gearing into wheels on the driving-shaft, so that the cylinders revolve simultaneously, their front ends being always maintained in the same position by the flanges of the rollers I, while the main body of each cylinder is at liberty to expand and contract under the influence of changes in temperature.

N is the furnace, the products of combustion from which permeate the chamber Q, containing the roasting-cylinders, before they pass off through the conduit T, as explained hereinafter, this chamber-Q, being bounded below by a partition, m, wliich protects the frame J and extends from the furnace to the outlet 01.

The outer end of each cylinder is open for the free entrance of the external air, which is prevented, by a plate, h, from gaining access to the chamber Q through the opening in the wall around the cylinders.

The lower end of one of the tubes G projects into the open end of each roasting-cylinder, as shown in Fig. 3, the spout being furnished with a weighted valve, t, which permits the ore to pass from the spout into the cylinder in proper and uniform quantities, the valve, with the ore which is always banked against it, forming a trap for preventing the hot air and gases from ascending the tube Gr.

It should be here understood that the conduit T communicates with exhausting mechanism, as more fully explained hereinafter.

The revolving roasting cylinders having been heated above the ignition-point of the ore by the fuel in the furnace, the ore is permitted to enter the said cylinders, where it is gradually brought to ignition, the internal ribs .1: of the cylinders continuously raising masses of the ore, and causing itto fall through the volumes of air induced to rush through the cylinders by the exhaust mechanism above alluded to. Hence the ore, Which,owing to the rush of air through the cylinders, progresses slowly through the same, is thoroughly oxidized before it reaches the inclined portion of the partition m.

The oxidized ore, escaping through the outlet d, falls into a box, W, and passes thence through a spout, y. preparatory to being ground, washed, andsubjected to the amalgamating process. In falling from the inclined plane m the roasted ore is brought into intimate contact with a coil or coils of pipe, L, through which cold. water is caused to circu; late. Hence the ore is cooled before it passes from the spout 3 At the outlet d there is a suitably-weighted valve, t, which permits the free escape of the her A, previously alluded to, the pulverized ore being dried in this chamber by contact with the tubes prior to being conveyed to the roasting-cylinders, in the manner heretofore explained.

The heated air, gases, &c., pass through the settlingchambers B 'aml 3, particles of ore J settling at the bottom of all these chambers, from which they may be removed from time to time.

When there is present in the ore arsenic or other substances which have to be saved or collected to prevent the dissemination of poisonous vapors, the gases are caused to pass upwardin a chamber, B, and take the zigzag course determined by perforated or grated shelves k, through which pass streams of water from a' tank, It, above, such of the vapors as may escape the influence of the cataract passing into the chamber B which communicates, as shown in Fig. 5, with the fan '40, the

bladeszofg the latter impelling the gases hot air, and products. of combustion upward through a suitable chimney into the external air. From the chamber B the water flows into a tank, X, in which the insoluble portions settle, the water; with. matter-imsolution passing into the tank X, wh i c h shouldcontain a coil for the circulation ofi GOId W'EbGH-OPOMIBI cooling device may be employed.

he: col w ter n. he anlt y be pumped into the tank on the top of the chamber B.

Particles of available ore will be deposited on the bottom of the chambers B, B, and B from which the ore may be removed from time to time into a cooling-reservoir, Y.

I claim as my invention 1. The combination of'theroasting-cylinder H'and feed-regulator F-wit-h the elev'atorO andthe preparatory dry ing chamberA, where- .in the ore is heated beio're passing-to the roast- 'ing-furnace, as set forth.

2. The combination of" the chamber Q and iits, valved outlet dwith the box- W; its cooliing-coil L, and'spout y.

g 3. The combination 'ofthe roasting cylinder or cylinders H, the rollers I" for supporting the same, andthe cooling-pipesm.

i 4". The combination of-theioastingcylinder; H with the feeding-spout Gj, ierminating;with- ,in the open endofthe said'cylind'er, and having a weighted valve, allsubstantially as set- -forth.

In testimony whereof" 1* have signed my. name to this specification in the presence of" two subscribing-witnesses.

- AUGUSTINE Bi GRQSBY:

Witnesses:

HEBMANN MoEssNER,

HmmY SMITH; 

